The present invention relates to a mobile phone subscriber identity module (SIM) card switching unit, and more particularly to a mobile phone SIM card switching unit that enables electrical connection of several different SIM cards on the switching unit to a mobile phone having only one SIM card socket via a transmission line of the switching unit, so that good communication quality over different mobile communication network systems can be conveniently obtained through only one mobile phone.
A conventional mobile phone, such as the commonly used GSM900 handset and GSM1800 handset, is provided with an internal socket for receiving a subscriber identity module (SIM) card provided by respective mobile communication network system providers. By putting an SIM card in the SIM socket in the mobile phone, a user is allowed to connect to and communicate or use other services over a specific mobile communication network.
The mobile communication network system providers do not necessarily establish their bases at the same sites to always provide good communication quality at all places. It is possible for a certain mobile communication network system provider to have bases established at some places and therefore provide better communication quality at these places but poorer at other places. To overcome this problem and to always have good communication quality over mobile communication networks, some users would carry two or more mobile phones. It is, of course, inconvenient for a user to carry so many mobile phones at one time.
It is therefore a primary object of the present invention to provide a mobile phone SIM card switching unit on which one or more SIM card sockets are provided to each receive an SIM card therein, and at least one switch is provided thereon to control the electrical connection of a desired SIM card on the switching unit to a mobile phone connected to the switching unit, so that a user needs only to operate the switch of the SIM card switching unit to quickly and conveniently switch among different mobile communication network systems to always obtain the best communication quality with only one single mobile phone.